The 2094 is a 2090 bundled with a 40MB drive.
The story about the Quantum's is true, the 40MB (and 20MB!) drives where full height 3.5" and sat next to the floppy drive, much like the MFM drives. Also note: the A2090 has no room for a drive, that means it also sat at the second floppy bay.
The latter 52MB (and 105MB) where Quantum LPS drives (Low Profile) which meant they could sit on the brand spanking new A2091 controller.
